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 A151921 Net gain in number of ON cells at stage n of the cellular automaton described in A079317. 2
 0, 1, 4, 0, 12, -8, 20, -8, 44, -40, 52, -40, 76, -64, 100, -64, 172, -168, 180, -168, 204, -192, 228, -192, 300, -288, 324, -288, 396, -360, 468, -360, 684, -680, 692, -680, 716, -704, 740, -704, 812, -800, 836, -800, 908, -872, 980, -872, 1196 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Start with cell (0,0) ON; at each succeeding stage the cells that share exactly one edge with an active cell change their state. LINKS David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.] N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA If n is even, a(n) = A079315(n) = A151914(n/2); if n is odd, a(n) = A147582((n+1)/2) - A151914((n-1)/2). First differences of A079317. CROSSREFS Cf. A079317, A079315, A139250, A151914, A147582. Sequence in context: A273795 A273858 A273485 * A273838 A273761 A273424 Adjacent sequences:  A151918 A151919 A151920 * A151922 A151923 A151924 KEYWORD sign AUTHOR N. J. A. Sloane, Aug 05 2009, Aug 06 2009 STATUS approved

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Last modified September 21 09:06 EDT 2021. Contains 347597 sequences. (Running on oeis4.)